One of my constant problems is that I over think a lot of my strokes. This results in hitting the ball late (and putting some kind of weird slice on it that goes to the left when I hit my 2 handed backhand). The problem is most obvious when I'm doing an overhead smash. When I over think an overhead, I hit it late, early, slice it, or miss it entirely. It's really getting to be an annoyance in my tennis so how do I stop the habit?